For precision laser surgical operations such as cataract surgery, the surgical instrument of choice is a handpiece including an optical fiber along which laser radiation is delivered to a site being treated and a vacuum aspiration arrangement for removing any debris resulting from the treatment. One particular example is a laser handpiece used for ophthalmic laser surgery operations such as cataract removal. In such a handpieces, aspiration of debris takes place via a tube or conduit while delivery of laser radiation is delivered by a fiber which extends along or through the tube with the tip of the fiber located proximate a distal aperture of the tube.
For reasons of precision, the aspiration tube must be relatively small in diameter. For example small enough to fit within the lens capsule of an eye for extracting therefrom debris remaining after a foreign body located in the lens capsule has been shattered or ablated by laser radiation in a lensectomy. In prior art handpieces, this relatively small diameter frequently results in clogging of the tube, with consequent interruption of an operation while the clogging is cleared or a clogged handpiece is replaced.
A further problem with prior-art aspirating handpieces is that they are often unsuitable, by virtue of the dimensions of the aspiration arrangement, for phases of an operation in which a higher precision or precise penetration is required without the need for simultaneous aspiration. Typically in such an operation a non-aspiration handpiece may be used to fragment a foreign object in a bodily cavity, and an aspirating handpiece used to ablate fragments of the foreign object and aspirate the ablation products from the cavity. This of course requires changing a handpiece during an operation.
Changing handpieces may be required many times during an operation thus adding significantly to the duration of the operation. This, combined with the cost of the additional handpieces adds to the cost of the operation. Further, constant insertion and removal of the different handpieces through an incision in the eye can cause excessive manipulation of sensitive intraocular tissue, potentially resulting in over hydration of the cornea.